The Impact of a Low or High Phosphate Diet on Phosphate and Calcium Excretion in Healthy People

NCT ID: NCT04013776

Last Updated: 2019-07-12

Basic Information

• Recruitment Status: UNKNOWN
• Clinical Phase: NA
• Total Enrollment: 20 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2017-05-01
• Study Completion Date: 2019-09-30

Brief Summary

Phosphate is present in many of the foods that the investigators eat and is required by many cellular processes. The kidneys are the only organ that excrete the extra phosphate from the diet that the body does not require. Phosphate is linked to vascular calcification and cardiovascular disease. Measures of serum phosphate do not reflect the burden of phosphate and are not sensitive to early changes in the way the kidneys eliminate phosphate. This study will determine whether the kidneys handle an oral phosphate load differently after 5 days of a low phosphate diet compared to 5 days of a high phosphate diet.

Detailed Description

In this study, participants will follow a low-phosphorus diet (750 mg) with a 500 mg calcium supplement for 5 days keeping a detailed diary of the foods eaten during this period. On the 5th day, the participant will undergo a 24 hour urine collection. Participants will present after an overnight fast for baseline blood and urine measurements. Then they will consume water containing 500 mg of phosphorus. Urine and blood will be collected every hour for 3 hours for measurement of phosphate and calcium and for measurement of hormones known to regulate phosphate and calcium including fibroblast growth factor-23, parathyroid hormone and vitamin D. One week later, participants will follow the same diet but will also receive a 1250 mg phosphorus supplement for 5 days. On the 5th day, urine will be collected for 24 hours. Participants will present again after an overnight fast and undergo the identical testing.

Conditions

Cardiovascular Diseases; Aging; Nutrient; Excess

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: OTHER
• Blinding Strategy: NONE

Study Groups

Phosphate supplemented diet

All participants will undergo phosphate testing after following a phosphate supplemented diet for 5 days

Group Type: ACTIVE_COMPARATOR

Phosphate supplemented diet

Intervention Type: DIETARY_SUPPLEMENT

Participants will be asked to follow a 5 day menu of 750 mg of phosphorus daily along with a daily sodium phosphorus supplement of 500 mg

Low phosphate diet

All participants will undergo phosphate testing after following a low phosphate diet for 5 days

Group Type: NO_INTERVENTION

No interventions assigned to this group

Interventions

Phosphate supplemented diet

Participants will be asked to follow a 5 day menu of 750 mg of phosphorus daily along with a daily sodium phosphorus supplement of 500 mg

Intervention Type: DIETARY_SUPPLEMENT

Other Intervention Names

sodium phosphate

Eligibility Criteria

Inclusion Criteria

• healthy
• between ages of 20 and 40

Exclusion Criteria

• known heart disease
• known diabetes
• pregnant
• breast-feeding

• Minimum Eligible Age: 20 Years
• Maximum Eligible Age: 40 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Clinical Evaluation Research Unit at Kingston General Hospital

OTHER

Sponsor Role: lead

Responsible Party

Dr. Rachel Holden

Professor of Medicine Queen's University

Responsibility Role: PRINCIPAL_INVESTIGATOR

Locations

Queen's University

Kingston, Ontario, Canada

Site Status: RECRUITING

Countries

Canada

Central Contacts

Rachel Holden, MD

Role: CONTACT

rachel.holden@kingstonhsc.ca

613-533-3134

Corinne Babiolakis, MSc

Role: CONTACT

csb8@queensu.ca

613-533-6000 ext. 79579

Facility Contacts

Rachel Holden, MD

Role: primary

rachel.holdne@kingstonhsc.ca

613-533-3134

Corinne Babiolakis, MSc

Role: backup

csb8@queensu.ca

613-533-6000 ext. 79579

Other Identifiers

DMED-2031-17

Identifier Type: -

Identifier Source: org_study_id